Adjective, or verb, often used to describe people with swagger. If you are getting ratchet, it means you are doing something crazy. People who get ratchet would typically have swagger as well. Also, you can be ratchet. Anybody associated with getting ratchet or being ratchet probably knows a thing or two about havin a good time.
were gettin' ratchet this weekend. im so ratchet. let's get ratchet